Improved railroad-switch



iV) SNN.

NJETERS. PHOTO-LITHOGRAPHER, WASHINGTON, D. C.

UNITED STATES PATENT OFFICE.

THOMAS S. MITCHELL, 0F PITTSBURG, PENNSYLVANIA.

IMPRovED RAILROAD-SWITCH.

Specification forming part of Letters Patent No.'56,432, dated July 17,1866.

To all whom 'it may concern:

Be it known that I, Trios. S. MITCHELL, of the city of Pittsburg, in thecounty of Allegheny and State of Pennsylvania, have invented a new andImproved Self-Acting Railroad- Switch; and I do declare that thefollowing is a full and exact description thereof, reference being hadto the accompanying drawings, and to the letters of reference markedthereon.

The nature of my invention is a railroadswitch-moving apparatus,automatic in its action, and which makes it impossible for any wagons,engines, cars, or trucks to runoff the tracks which are connected withsaid switch.

In my drawings, Figure l is a top view ot' my improvedrailroad-switch-moving apparatus and switch. Fig. 2 is a detail, on anenlarged scale, of the part X of Fig. 4. Fig. 3 is a longitudinalsectional view, in elevation, of my improved switch moving apparatusthrough the line Y Y; and Fig. 4 is a transverse sectional elevation 0fthe same through the line Z Z.

A is the main track or road, and B is the` branch track or road. a and aare the rails of the main track A. b b are the rails of the track B. C Care the movable rails of the switch, which are pivoted at the points O Oin the usual manner, and are moved by the bar D. The bar D is connectedto two links, E and F, by center pins or bolts, jf, and the point G isheld by a stationary bolt or pin, around which it can swing. The middleof the links E F is connected to a short link, H, which is connected bya bolt to the bar I, so that if the said bar I is moved in the directionofthe black arrow it will act on the links E and F, and they will, bypulling on the bar D, move the switch in the position indicated by thered lines. At the end J of the barItliere is an ordinary lever withstand and quadrant, only the quadrant has but one notch7 K, for lookin gthe lever Q in the position for having the switch closed, so that whenthe lever Q is used to open the switch by hand it cannot be used to lockthe switch open, and the bar Ihas along slot at the point J, forallowing free motion to the bar I in the direction of the black arrow,even when the lever Q is locked.

It B are levers passing in square mortises in the bar I, which arefastened to two shafts, 1' i", so that if the arms B R are made tovibrate they will move the bar 1 in the direction of the black or redarrows.

At right angles with the arms B B, and also fastened to the shafts o"o", are four small levers or arms, S S S S, upon which rests the frame TT, and extending opposite to them are two levers with counter-weights UU, sufficient to overcome the weight of the frame T T, lift them up, andalso move the bar I in the direction of the red arrow and close theswitch. These levers and Weights U can be replaced by one or moresprings, which will answer the same purpose.

Y V are two pieces of steel, which are placed by the side of the top ofthe movable frames T T, and serve the purpose of preventing any stonesor other obstructions from lodging under the pieces T T and preventingtheir free action. It is also usedv to prevent the broad-face wheel Pfrom acting on the piece T, Fig. 2, in the case where the wheel, beingworn and being as a double-flange wheel, might act on the piece Twhennot intended to do so. The wheel P on Fig. 2 demonstrates how the weightwould in that case be received on the piece Y and not on the piece T, asit would do if the piece V were not there.

The operation of my automatic switch-moving apparatus is at once simpleand efficient, and no train can run oft' the track with such 'a switchattachment.

If a train is on the main track A, ruiming in either direction, itcannot run oft the track, for the switch is kept closed by the weights UU or springs, and it cannot be left open by mistake, as there are nolock-notches to the quadrant to keep the switch open, and unless keptopen by the application of manual force on the lever Q it will alwaysily back andbe held securely closed by the springs or weights U U.

The only train that could possibly run off the track would be one comingfrom the track B in the direction of the arrow on that track, but assoon as the first wheel of that train would arrive at the point M thewheels would be in the position represented by the wheelN in Fig. 2, andthe whole weight of the train bearing on the anges T T will depress theframes in the position indicated in red in Fig. 3, raise the weights UU, and open the switch, as already described, so that the train couldnot by any means run off the track. As soon as the last wheel of thetrain reaches the point m the switch is relieved from any Weight, andyielding to the influence of the Weights U U or springs, it Will closeand be perfectly safe.

What I claim as my invention, and desire to secure by Letters Patent ofthe United States, 1s-

l. The automatic switch-moving apparatus composed of the bar D, links EF H, bar I, 1e- Vers R R, shafts r i, arms S yS, frames T T, and WeightsU U, or their equivalents, when they are arranged and operating asspecified.

action of the Weight of the train itself on the frames TT, in the mannerdescribed, and for the purpose of preventing such train from runningoft' the track.

THOMAS S. MITCHELL. [L. s.)

Witnesses:

H. P. GENGEMBER, OAMiLLE DEY.

